<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>10  vue渲染问题</title>
    <script src="./js/vue.js"></script>
</head>

<body>
    <div id="app">
        <h2 ref="h2">
            {{num}}
        </h2>
        <button @click="getValue">获取</button>
        

    </div>
</body>

<script>
 

    new Vue({
        el: "#app",
        data: {
            num: 100,
        },
        methods:{
            getValue(){
                this.num = 999;

            },
        },
    })



</script>

</html>